1. Field of the Invention
The present invention relates to an image processing apparatus and, more particularly to an image processing apparatus for processing image data with color information.
2. Related Background Art
A conventional color printing apparatus was so constructed that a predetermined color reproduction process was performed, and had no any other operation modes to simplify the color reproduction process for printing.
Accordingly, when the predetermined color reproduction process is complicated, there were the following defects especially in processing color image data in the above conventional example:
(1) It takes time to paint because the complicated process must be repeated again and again. PA1 (2) The color tone of the obtained picture often does not conform to the desired one, but requires a color correction process. The desired painting result is usually not obtained once.
Conventionally in this type of apparatus, there was a color correction processing device for an apparatus for recording color information such as an ink jet type or an electrophotography type.
As the color correction method in such an apparatus, a method for a masking process whereby an image on a CRT screen or scanner draft image is color matched with a recording image on a recording medium, or a black generation and under color removal (UCR) method for inking on a recording image, etc. are known.
In the above conventional example, however, a natural picture is mainly processed, and therefore even for an object image, in which characters and graphic forms prepared by a computer are mixed with the natural picture, a color correction process similar to the above-mentioned process is performed. In this case, the conventional example had the defect that the masking, black generation, under color removal, etc. are performed also for characters, which should be recorded all in black, and graphic forms, which should be painted out in a color specified by a color sample.
On the other hand, a technique that detects a black edge in image data which have been input from a reader, and prints unmasked black data on that black edge, is disclosed by U.S. Pat. No. 5,126,838. However, there was room for improvement in the detection method, etc. for the black edge.
Also, a technique that selects whether or not the masking and under color removal process should be performed in accordance with the input command data, is disclosed by U.S. Pat. No. 4,958,219. However, there was room for improvement in the mode selection, etc.